Improvement in spark-extinguishers



J. JOHNSON, Spark-Extinguisher No. 204,739. Pate nted June H, 1878.

* WM yi mafi'm/ 2 3 UNITED STAT S PATENT OFFICE.

JOHN JOHNSON, OF BLOOMFIELD, CALIFORNIA.

IMPROVEMENT IN SPARK-EXTINGUISHERS.

Specification forming part of Letters Patent No- 204,739, dated June 11,1878 application filed September 16, 1876.

To all whom it may concern:

Be it known that I, JOHN JOHNSON, of Bloomfield, county of Sonoma, andState of California, have invented an Improved Spark-Extin guisher and Ido hereby declare the following to be a full, clear, and exactdescription thereof, reference being had to the accompanying drawings.

My invention relates to certain improvements in that class ofspark-extinguishers used in the smoke-stacks of engine-furnaces, and inwhich water is employed in various forms to kill or quench the sparks.

It consists in the employment of a rosesprinkler having minuteperforations, through which water is forced upward in the same directionas the sparks move.

It also consists in a novel arrangement of the perforations and the topof the sprinkler, in order to prevent the minute jets from beingreunited by the action of the exhaust, so as to form large drops orstreams of water, as this will reduce the efficiency of theextinguisher, besides throwing the water and soot over all the machinerynear.

In the dry harvest-fields where there is a nearly rainless climate, ifan engine is used, it is extremely dangerous to the surroundingcombustible material, and water is almost always scarce, so that theamount used for an extinguisher of this class, in addition to thatrequired for the engine, is an important feature.

By the use of my device I am enabled to perfectly quench the sparks witha small quantity of water.

Beferrin g to the accompanying drawings for a more complete explanationof my invention, A is the boiler, B the furnace, and O the smokestack,of an engine. I have not shown in this case anything more than arepresentation of the parts of the engine sufficient to show theattachment of my device. This consists of a rose or sprinkler, F, ofpeculiar construction, which is supported above the exhaust-nozzle inthe smoke-stack, and has a pipe, D, leading to it from the feed-pumpE,which is, in the present case, represented as secured to one side ofthe boiler.

It will be seen that any suitable forcing apparatus may be employed; butthe ordinary feedpump is usually the most convenient, and when my deviceis employed with it it serves to re lieve the pump from the air whichwill collect when the engine is stopped. It also serves to keep the pumpin better working order by carrying more water.

The rose or sprinkler does not differ in general appearance from othersprinklers of this class, although it is different in some points ofconstruction. It consists of a convex top, a

hollow conical body, and a not at the base,

into which the pipe D is screwed. The convex top is perforated withholes as minute as possible, and they are arranged so as to alter nateand not stand in radial lines, because the force of the exhaust-steammoving directly up the stack has a tendency to throw the jets which havebeen spread by the shape of the sprinkler back toward the center, andalso to unite them into larger streams, instead of shattering them intoa mist, as has been supposed. The hole in the nut is smaller than thatin the pipe, and thus concentrates the stream from that point, so thatit strikes the unperforated center of the convex top. This prevents theformation of a central stream of solid water, and aids in the separationof water into jets.

I am aware that various attempts have been made to use water to quenchthe sparks and cinders before they leave the stack, either by throwing athin sheet of water across the stack, or by discharging the water intothe exhaustpipe, or by throwing it into the stack by some form of jetnot specially contrived. These have all been failures, because inpractice it will be found that there is a tendency of the water toconcentrate into larger streams or drops, instead of being formed into amist by the force of the steam; and this not only fails to quench thesparks, but scatters dirty water and soot all about the engine.

My experience has proved that the water must be reduced to the minutestform possible before being discharged into the stack, and then preventedfrom reuniting and I effect it with my apparatus so thoroughly that noappreciable moisture is thrown out,'but a dry mass of straw may be laidupon the top of the stack, and it will not be ignited.

It is a well-known fact that wet steam will quench the sparks betterthan a sheet or streams of water; and experiencehas also shown thatwater in the form of sheets or streams will also impede the draft tosuch an extent as to make it impossible to keep up steam with the dampfuel which it is often necessary to use. With my device the water ispractically so thoroughly united with the steam, which is often highlysuperheated, that it becomes, practically, a part of it, and acts as wetsteam. This will eflectually quench the sparks, and n0 bonnet will beneeded, thus avoiding the expense and the time lost in cleaning when thebonnet becomes foul.

Having thus described my invention, what JOHN JOHNSON. [L. s.]

Witnesses:

V. STILLWELL, O. H. PALMER.

